Door operator



Nov. 17, 1942. I e. E. HULSE 2,301,950

DOOR OPERATOR Filed Feb. 8, 1940 INVENTOR geozye E. Hulse h M ATI'ORNEAYZ Patented Nov. 17, 1942 DOOR OPERATOR George E. Hulse, New Haven, Conn., assignor to The Safety Car Heating and Lighting Com-- pany, 1110., a corporation of Delaware Application February 8, 1940, Serial 'No. 317,813

3 Claims.

This invention relates to door operating apparatus and more particularly to automatic apparatus of this character.-

One of the objects of this invention is to provide door operating apparatus which is relatively simple in construction and operation, and which operates reliably without need of repeated adjustment or repair. Another object is to provide apparatus of the above nature'capable of operating economically with respect to power requirements. Another object is to provide automatic apparatus of the above nature. Other objects will be in part apparent and in part pointed out hereinafter.

The invention accordingly'consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in thefollowing claims.

In the drawing wherein there is shown two embodiments of my invention,

Figure 1 is afragmentary' top plan view of a door and operator therefor;

Figure 2 is a schematic view of the actuating mechanism for the operator of Figure 1, together with a control system therefor; and,

Figure3 is a schematic view, similar to Figure 2, of a modified control system for the operator actuating mechanism.

Similar reference characters refer to similar parts throughoutthe various views of the drawmg.

Automatic door operation has heretofore been attempted by various types of mechanism which, because of structural complexity, high cost and excessive power requirements have proved commercially impractical. is often desirable in situations where limited space precludes the installation of the bulkier portions of the operating mechanism. Under suchconditions, conventional automatic operators areaccordingly useless. Still other undesirable features characterize available automatic operators, and it is to the preclusion thereof that my automatic operator is directed.

'With reference to Figure 1, a door 16 is hinged to a frame H or the like by hinges 12 so as sto swingbetween open and closed positions with respect to an opening l3 in frame-I I. An operator, generally indicated at M, is pivotally connected at one end thereof to door l and at the other end thereof to a portion, not shown, of frame II- or to the supporting structure (not shownl-adjacent thereto: Opera-tor I4 is ener Automatic door operation gizable, as will be hereinafter described, to swing door II] as indicated by the arrow in Figure 1.

Operator l4 includes a cylinder [5 within which a piston I 6 is reciprocably disposed. Connected to piston I6 is a rod H which extends from the open end of cylinder [5 and is connected to a housing l8 or the like in which is disposed a spring (not shown), the purpose of which will be described hereinafter. Housing I8 is pivotally connected to a strut 19 or the like extending from a bracket 20 which is suitably secured to the upper portion of door I0. Thus it will be seen that the right-hand end of operator M, as viewed in Figure 1, is pivotally secured to the door. The left-hand end of the operator is provided with a plate-like extension 2| in which a hole 22 is formed, which hole is adapted to re ceive a suitable pin (not shown) or other device whereby the left-hand end of operator I4 is pivoted to the structure (not shown) adjacent frame I l. The closed end of cylinder I5 is provided with an opening 23 to which a flexible tube 24 or the like is connected, the other end of tube 24 being connected to a pipe 25. c

As viewed in Figure 2, pipe 25 may be of any desirable length so that the various mechanisms shown in Figure 2 may be located in any desirable place near to or at a distance from door It! (Figure 1). Referring back to Figure 2, pipe 25 communicates by way of a check valve 25 with a pipe 21 connected to the outlet end of a pump 28. Pump 28 may be operated in any suitable manner, but preferably by an electric motor 29. Check valve 26 is so constructed as freely to allow flow of fluid such as oil from pump 28 in the direction of the arrow (Figure 2) through pipe 25 and flexible coupling 24 (Figure 1) into cylinder I5 in back of piston 16. As the oil is forced into the cylinder, piston I6 is accordingly moved to the right, as viewed in Figure 1, causing door ID to swing open.

As hereinbefore noted, housing i8 includes a spring which is so connected to the housing and strut I9 that the spring is loaded or wound while the door is opening. Thus, when the oil pres sure is taken off piston IE, the spring in housing i8 has sufficient power to swing the door in closing direction. During this movement of the door, piston I6, of course, moves to the left in cylinder I5, forcing the oil therefrom through coupling 24 and pipe 25 through check valve 25 (Figure 2). The check valve, however, will not freely pass the fluid inthis direction of flow, but rather meters the flow so as to provide a retarded clos ing action of the door under the impetus of the spring in housing I8 (Figure 1).

Check valve 26 includes a gate 26a pivoted as at 261) and having an end portion 260 adapted to abut against a stop 26d when in its closed position. However, when the valve gate 26a is in its closed position it is slightly spaced from the top of pipe 21 so that fluid flowing from pipe 25 cannot flow freely through check valve 26 and into pipe 21, this return flow of fluid accordingly being metered, thus providing the retarded closing action of the door under the impetus of the spring as noted hereinabove.

It is, of course, understood that other types of valve structure may be employed to obtain similar results. Pump 28 may, if desired, be of the type which readily permits oil flow therethrough when not in operation, and accordingly a re verse flow of oil through check valve 23 in pipe 21 may pass freely through the pump.

Still referring to Figure 2, a pipe 38 branches from pipe 21 and is connected to a check valve 3| in turn connected to a pipe 32 which extends downwardly into a reservoir 33 preferably substantially to the bottom thereof. Reservoir 33 is connected to pump 28 as by a pipe 34 leading from the bottom of reservoir 33 to the inlet of the pump. Check valve 3| is so designed and operated as will be more fully described hereinafter, that during door opening operation, i. e., while pump 23 is pumping oil through pipe 2'5, this valve is closed so as to preclude bypassing of oil from pipe 2'! 'to reservoir 33. If, however, resistance exceeding a predetermined maximum is applied to door It) (Figure 1) during its opening movement, the flow of fluid through pipe 27 is bypassed through pipe 33 and check valve 3| into reservoir 33 by way of pipe 32 as the check valve is designed to permit flow of oil therethrough when the oil pressure extends a predetermined maximum. This predetermined maximum oil pressure bears a direct relation to the predetermined maximum resistance referred to,

Pump 28 is, of course, constantly supplied with oil from the bottom of reservoir 33. It will thus be seen that through the provision of check valve 3|, damage to the operator mechanisms is precluded when and if the door meets an obstacle during its opening operation. Furthermore, personal injury by the opening movement of the door is precluded as check valve 3| (Figure 2) is so designed as to bypass the oil before the door can exert injurious pressure. It may also be seen that as operator I4 is connected to pump 28 by piping which may be of any desired length, the pump, its motor, reservoir 33 and the other parts associated therewith may be located'as desired. Accordingly, the bulkier parts of my apparatus may be located distantly from the door to be operated and hence, may be advantageously utilized when space adjacent the door is at a premium.

To effect automatic operation of the mechanisms hereinbefore described, I have provided the control circuit shown in Figure 2. This circuit includes a suitable source of current 35 which is connected by lines 33 and 3'1 to motor 29 to effect energization thereof upon the closing of a switch 38 in line 31. A line 39 connected to line 37 leads to one side of a solenoid generally indicated at 20. The other side of solenoid 33 is connected to line 33 by a line 4|. When solenoid 46 is energized, its armature closes check valve 3|, i. e., it closes the valve against flow of oil therethrough at normal operating pressure. 7

into reservoir 33 (Figure 2).

To effectuate the operation of check valve 3| as described above, this valve includes a gate generally indicated at 60, pivoted as at 6|, so as to be movable between the full and dotted line positions shown in Figure 2. Gate 60 preferably includes an arm 62 which may be moved against the open end of pipe 30 to prevent flow of fluid therefrom into the body of valve 3 I. Gate 60 also includes an arm 63 which is pivotally connected to the plunger Ella of solenoid All so that when the solenoid is energized gate 60 is held in its closed or full line position. Upon deenergization of the solenoid plunger 40a may drop, permitting movement of the valve gate to its open or dotted line position. Thus, when the solenoid circuit is energized as hereinbefore described, passage of fluid through pipe 30 at normal operating pressure is precluded. If, however, the oil pressure exceeds its normal value, gate 50 will be forced open against the bias of solenoid 4i), permitting the oil to by-pass through pipe 32 into reservoir 33. It is, of course, understood that other types of valve may be used to obtain similar results.

Preferably the door is provided with an automatically controlled latch generally indicated at 52 in Figure 2. This latch is controlled by a solenoid 43, connected across lines 39 and 4| by lines 44 and 45, respectively. Hence, when lines 39 and 4| are energized through the closing of switch 38, solenoid 43 is energized automatically to disengage latch 42 and permit the door to open.

In operation, switch 38 (Figure 2) is manually closed and motor 29 and solenoid 40 are energized. Energization of the motor causes pump 28 to pump oil through pipes 21 and 25 into cylinder I5 (Figure 1) to effect opening of the door. Energization of solenoid 4U closes check valve 3| to prevent bypass of the oil into reservoir 33. Closing of switch 38 also energizes solenoid 43 which unlatches the door to permit its opening movement. When the door has opened sufliciently to permit passage through its opening, switch 38 is opened to deenergize motor 29 and solenoids 4!) and 43. Upon this deenergization, pump 28 stops, check valve 3| opens, and latch 42 is released to automatically lock the door when it closes. The spring in housing l8 (Figure 1) swings the door in closing direction and causes oil to flow back at a retarded rate, because of check valve 23, through pipe 25 (Figure 2) and into reservoir 33, either by way of check valve 3| which is now open, or by way of pump 28 and pipe 33, if the pump is of a character that will allow oil to flow therethrough when inactive.

With the modified control system shown in Figure 3, the door completely opens before it closes, regardless of the manual operation of the switches provided. In this system, check valve 3| is operated by solenoid 40, as described hereinabove, and latch 42 is operated by its solenoid 33, also as described; In this form of the control apparatus, however, I provide a magnetically retained push button switch, generally indicated at 43, which is connected in series with a line 4'! which connects one side of motor 29 and solenoids 40 and 43 through switch 45 and lines 48 and 49 to the source of current 35. I also provide a door operated switch 50 in line 49, which is so constructed that when the door opens to a predetermined point, it opens the switch. Switch 50 is closed at all other times.

Push button switch 46 includes a push button mounted on the armature 52 of a solenoid 53. Also attached to the push button is a contact plate 54 adapted to bridge a pair of contact points 55 and 56 which are respectively connected to solenoid 53 and line 41. Contact points 55 and 55 are electrically connected when push button 5| is pressed, and a circuit is closed as follows: source of current 35, line 49, door switch 59. line 48, solenoid 53, contact point 55, contact plate 54, contact point 55, line 41, motor 29 and back to source 35 by a line 51. The energizing of line 41 also completes the circuits of solenoids 40 and 43 which are connected at their other sides to the battery 35 through lines 39 and 44, respectively. When these circuits are made, solenoid 53 is, of course, energized and armature 52 is held thereby until the solenoid coil is deenergized. Accordingly, contact plate 54 is held across contact points 55 and 56. During this position of the contact plate, motor 29 is energized, and the door is opened, as hereinbefore described. When, however, the door reaches its open position, it automatically opens switch 59 to break the circuit hereinbefore described causing deenergization of solenoid 53, and accordingly retraction of contact plate 54 from points 55 and 5B. The door thus may swing closed under the impetusof its spring, as described. Thus, it will be seen that in this modified form of control, the door, subsequent to manual operation of push button switch 5| is under complete automatic control and necessitates no further manual attention to complete its cycle of operation.

Accordingly, I have provided door operating apparatus which attains the several objects hereinbefore set forth in a thoroughly practical and efiicient manner.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In apparatus of the character described for opening a door which is provided with door closing means for automatically reclosing the door after the door has been opened, the combination of, a cylinder-piston unit having one end mounted upon the door frame and having the other end connected so that its movement is effective to open the door, a liquid supply-and-return conduit connected to deliver liquid to said cylinder to thereby move said piston and to receive the liquid from the cylinder, a liquid supply reservoir, a pump operable to pump liquid from said reservoir through said conduit to said cylinderpiston unit, a liquid return and by-pass conduit connected to said liquid supply-and-return conduit adjacent the outlet of said pump and hav ing a discharge end connected to discharge liquid into said reservoir, a double acting valve means positioned in said by-pass conduit having an open position in which it permits liquid to pass freely and a closed position in which it permits liquid to pass only after the pressure within the conduit is raised beyond a predetermined value, motive means to operate said pump means, and manually operable control means to substantially simultaneously render said motive means operable to operate said pump and to move said valve means to its closed position and to thereafter render said motive means inoperative simultaneously with the moving of said valve means to the open position.

2. Apparatus as described in claim 1, wherein said motive means is an electric motor driven from a battery system and wherein said control means includes a normally closed limit switch adapted to be opened by the approach of the door to its open position and an interlock switch in series therewith, said interlock switch being operative to hold said motive means in operation until the door has been moved to its open position to thereby open said door limit switch.

3. Apparatus of the character described in claim 1, wherein a check valve is positioned in said liquid supply-and-return conduit between its connection with said by-pass conduit and said cylinder-piston unit and adjacent said by-pass conduit, said check valve being operative to permit free flow of liquid toward said cylinder-piston unit and to permit restricted return flow of liquid from said cylinder-piston unit.

GEORGE E. HULSE. 

